Each year, nearly 27,000 adults and more than 2,000 children in the United States learn that they have leukemia. Leukemia is characterized by large numbers of abnormal blood cells, generally white blood cells.
There are several types of leukemia. Leukemia is either acute or chronic. In acute leukemia, the abnormal blood cells are blasts that remain very immature and cannot carry out their normal functions. The number of blasts increases rapidly, and the disease gets worse quickly. In chronic leukemia, some blast cells are present, but in general, these cells are more mature and can carry out some of their normal functions. Also, the number of blasts increases less rapidly than in acute leukemia. As a result, chronic leukemia gets worse gradually.
Leukemia can arise in either of the two main types of white blood cells—lymphoid cells or myeloid cells. When leukemia affects lymphoid cells, it is called lymphocytic leukemia. When myeloid cells are affected, the disease is called myeloid or myelogenous leukemia. Acute lymphocytic leukemia (ALL) is the most common type of leukemia in young children. This disease also affects adults, especially those age 65 and older. Acute myeloid leukemia (AML) occurs in both adults and children. This type of leukemia is sometimes called acute nonlymphocytic leukemia (ANLL). Chronic lymphocytic leukemia (CLL) most often affects adults over the age of 55. It sometimes occurs in younger adults, but it almost never affects children. Chronic myeloid leukemia (CML) occurs mainly in adults. A very small number of children also develop this disease. Hairy cell leukemia is an uncommon type of chronic leukemia.
Common symptoms of leukemia include fever, chills, and other flu-like symptoms, weakness and fatigue, frequent infections, loss of appetite and/or weight, swollen or tender lymph nodes, liver, or spleen, easy bleeding or bruising, small red spots (called petechiae) under the skin, swollen or bleeding gums, sweating, especially at night; and/or bone or joint pain.
Treatment varies with the type of leukemia and the age and medical status of the patient. Treatment options include chemotherapy, radiation, bone marrow transplantation, and biological therapy such as interferon.
Survival rate varies based on the type and stage of leukemia as well as the patient's age and health. Even with new advances in care, patients with many types of leukemia continue to have low long-term survival rates. What is needed are improved treatment methods.